<?php
/*=======================================================================
 // File:        JPGRAPH_UTILS.INC
 // Description: Collection of non-essential "nice to have" utilities
 // Created:     2005-11-20
 // Ver:         $Id: jpgraph_utils.inc.php 1777 2009-08-23 17:34:36Z ljp $
 //
 // Copyright (c) Aditus Consulting. All rights reserved.
 //========================================================================
 */

//===================================================
// CLASS FuncGenerator
// Description: Utility class to help generate data for function plots.
// The class supports both parametric and regular functions.
//===================================================
class FuncGenerator {
	private $iFunc='',$iXFunc='',$iMin,$iMax,$iStepSize;

	function __construct($aFunc,$aXFunc='') {
		$this->iFunc = $aFunc;
		$this->iXFunc = $aXFunc;
	}

	function E($aXMin,$aXMax,$aSteps=50) {
		$this->iMin = $aXMin;
		$this->iMax = $aXMax;
		$this->iStepSize = ($aXMax-$aXMin)/$aSteps;

		if( $this->iXFunc != '' )
		$t = 'for($i='.$aXMin.'; $i<='.$aXMax.'; $i += '.$this->iStepSize.') {$ya[]='.$this->iFunc.';$xa[]='.$this->iXFunc.';}';
		elseif( $this->iFunc != '' )
		$t = 'for($x='.$aXMin.'; $x<='.$aXMax.'; $x += '.$this->iStepSize.') {$ya[]='.$this->iFunc.';$xa[]=$x;} $x='.$aXMax.';$ya[]='.$this->iFunc.';$xa[]=$x;';
		else
		JpGraphError::RaiseL(24001);//('FuncGenerator : No function specified. ');

		@eval($t);

		// If there is an error in the function specifcation this is the only
		// way we can discover that.
		if( empty($xa) || empty($ya) )
		JpGraphError::RaiseL(24002);//('FuncGenerator : Syntax error in function specification ');

		return array($xa,$ya);
	}
}


//=============================================================================
// CLASS DateScaleUtils
// Description: Help to create a manual date scale
//=============================================================================
define('DSUTILS_MONTH',1); // Major and minor ticks on a monthly basis
define('DSUTILS_MONTH1',1); // Major and minor ticks on a monthly basis
define('DSUTILS_MONTH2',2); // Major ticks on a bi-monthly basis
define('DSUTILS_MONTH3',3); // Major icks on a tri-monthly basis
define('DSUTILS_MONTH6',4); // Major on a six-monthly basis
define('DSUTILS_WEEK1',5); // Major ticks on a weekly basis
define('DSUTILS_WEEK2',6); // Major ticks on a bi-weekly basis
define('DSUTILS_WEEK4',7); // Major ticks on a quod-weekly basis
define('DSUTILS_DAY1',8); // Major ticks on a daily basis
define('DSUTILS_DAY2',9); // Major ticks on a bi-daily basis
define('DSUTILS_DAY4',10); // Major ticks on a qoud-daily basis
define('DSUTILS_YEAR1',11); // Major ticks on a yearly basis
define('DSUTILS_YEAR2',12); // Major ticks on a bi-yearly basis
define('DSUTILS_YEAR5',13); // Major ticks on a five-yearly basis


class DateScaleUtils {
	public static $iMin=0, $iMax=0;

	private static $starthour,$startmonth, $startday, $startyear;
	private static $endmonth, $endyear, $endday;
	private static $tickPositions=array(),$minTickPositions=array();
	private static $iUseWeeks = true;

	static function UseWeekFormat($aFlg) {
		self::$iUseWeeks = $aFlg;
	}

	static function doYearly($aType,$aMinor=false) {
		$i=0; $j=0;
		$m = self::$startmonth;
		$y = self::$startyear;

		if( self::$startday == 1 ) {
			self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
		}
		++$m;


		switch( $aType ) {
			case DSUTILS_YEAR1:
				for($y=self::$startyear; $y <= self::$endyear; ++$y ) {
					if( $aMinor ) {
						while( $m <= 12 ) {
							if( !($y == self::$endyear && $m > self::$endmonth) ) {
								self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
							}
							++$m;
						}
						$m=1;
					}
					self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
				}
				break;
			case DSUTILS_YEAR2:
				$y=self::$startyear;
				while( $y <= self::$endyear ) {
					self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
					for($k=0; $k < 1; ++$k ) {
						++$y;
						if( $aMinor ) {
							self::$minTickPositions[$j++] = mktime(0,0,0,1,1,$y);
						}
					}
					++$y;
				}
				break;
			case DSUTILS_YEAR5:
				$y=self::$startyear;
				while( $y <= self::$endyear ) {
					self::$tickPositions[$i++] = mktime(0,0,0,1,1,$y);
					for($k=0; $k < 4; ++$k ) {
						++$y;
						if( $aMinor ) {
							self::$minTickPositions[$j++] = mktime(0,0,0,1,1,$y);
						}
					}
					++$y;
				}
				break;
		}
	}

	static function doDaily($aType,$aMinor=false) {
		$m = self::$startmonth;
		$y = self::$startyear;
		$d = self::$startday;
		$h = self::$starthour;
		$i=0;$j=0;

		if( $h == 0 ) {
			self::$tickPositions[$i++] = mktime(0,0,0,$m,$d,$y);
		}
		$t = mktime(0,0,0,$m,$d,$y);

		switch($aType) {
			case DSUTILS_DAY1:
				while( $t <= self::$iMax ) {
					$t = strtotime('+1 day',$t);
					self::$tickPositions[$i++] = $t;
					if( $aMinor ) {
						self::$minTickPositions[$j++] = strtotime('+12 hours',$t);
					}
				}
				break;
			case DSUTILS_DAY2:
				while( $t <= self::$iMax ) {
					$t = strtotime('+1 day',$t);
					if( $aMinor ) {
						self::$minTickPositions[$j++] = $t;
					}
					$t = strtotime('+1 day',$t);
					self::$tickPositions[$i++] = $t;
				}
				break;
			case DSUTILS_DAY4:
				while( $t <= self::$iMax ) {
					for($k=0; $k < 3; ++$k ) {
						$t = strtotime('+1 day',$t);
						if( $aMinor ) {
							self::$minTickPositions[$j++] = $t;
						}
					}
					$t = strtotime('+1 day',$t);
					self::$tickPositions[$i++] = $t;
				}
				break;
		}
	}

	static function doWeekly($aType,$aMinor=false) {
		$hpd = 3600*24;
		$hpw = 3600*24*7;
		// Find out week number of min date
		$thursday = self::$iMin + $hpd * (3 - (date('w', self::$iMin) + 6) % 7);
		$week = 1 + (date('z', $thursday) - (11 - date('w', mktime(0, 0, 0, 1, 1, date('Y', $thursday)))) % 7) / 7;
		$daynumber = date('w',self::$iMin);
		if( $daynumber == 0 ) $daynumber = 7;
		$m = self::$startmonth;
		$y = self::$startyear;
		$d = self::$startday;
		$i=0;$j=0;
		// The assumption is that the weeks start on Monday. If the first day
		// is later in the week then the first week tick has to be on the following
		// week.
		if( $daynumber == 1 ) {
			self::$tickPositions[$i++] = mktime(0,0,0,$m,$d,$y);
			$t = mktime(0,0,0,$m,$d,$y) + $hpw;
		}
		else {
			$t = mktime(0,0,0,$m,$d,$y) + $hpd*(8-$daynumber);
		}

		switch($aType) {
			case DSUTILS_WEEK1:
				$cnt=0;
				break;
			case DSUTILS_WEEK2:
				$cnt=1;
				break;
			case DSUTILS_WEEK4:
				$cnt=3;
				break;
		}
		while( $t <= self::$iMax ) {
			self::$tickPositions[$i++] = $t;
			for($k=0; $k < $cnt; ++$k ) {
				$t += $hpw;
				if( $aMinor ) {
					self::$minTickPositions[$j++] = $t;
				}
			}
			$t += $hpw;
		}
	}

	static function doMonthly($aType,$aMinor=false) {
		$monthcount=0;
		$m = self::$startmonth;
		$y = self::$startyear;
		$i=0; $j=0;

		// Skip the first month label if it is before the startdate
		if( self::$startday == 1 ) {
			self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
			$monthcount=1;
		}
		if( $aType == 1 ) {
			if( self::$startday < 15 ) {
				self::$minTickPositions[$j++] = mktime(0,0,0,$m,15,$y);
			}
		}
		++$m;

		// Loop through all the years included in the scale
		for($y=self::$startyear; $y <= self::$endyear; ++$y ) {
			// Loop through all the months. There are three cases to consider:
			// 1. We are in the first year and must start with the startmonth
			// 2. We are in the end year and we must stop at last month of the scale
			// 3. A year in between where we run through all the 12 months
			$stopmonth = $y == self::$endyear ? self::$endmonth : 12;
			while( $m <= $stopmonth ) {
				switch( $aType ) {
					case DSUTILS_MONTH1:
						// Set minor tick at the middle of the month
						if( $aMinor ) {
							if( $m <= $stopmonth ) {
								if( !($y==self::$endyear && $m==$stopmonth && self::$endday < 15) )
								self::$minTickPositions[$j++] = mktime(0,0,0,$m,15,$y);
							}
						}
						// Major at month
						// Get timestamp of first hour of first day in each month
						self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);

						break;
					case DSUTILS_MONTH2:
						if( $aMinor ) {
							// Set minor tick at start of each month
							self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
						}

						// Major at every second month
						// Get timestamp of first hour of first day in each month
						if( $monthcount % 2 == 0 ) {
							self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
						}
						break;
					case DSUTILS_MONTH3:
						if( $aMinor ) {
							// Set minor tick at start of each month
							self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
						}
						// Major at every third month
						// Get timestamp of first hour of first day in each month
						if( $monthcount % 3 == 0 ) {
							self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
						}
						break;
					case DSUTILS_MONTH6:
						if( $aMinor ) {
							// Set minor tick at start of each month
							self::$minTickPositions[$j++] = mktime(0,0,0,$m,1,$y);
						}
						// Major at every third month
						// Get timestamp of first hour of first day in each month
						if( $monthcount % 6 == 0 ) {
							self::$tickPositions[$i++] = mktime(0,0,0,$m,1,$y);
						}
						break;
				}
				++$m;
				++$monthcount;
			}
			$m=1;
		}

		// For the case where all dates are within the same month
		// we want to make sure we have at least two ticks on the scale
		// since the scale want work properly otherwise
		if(self::$startmonth == self::$endmonth && self::$startyear == self::$endyear && $aType==1 ) {
			self::$tickPositions[$i++] = mktime(0 ,0 ,0, self::$startmonth + 1, 1, self::$startyear);
		}

		return array(self::$tickPositions,self::$minTickPositions);
	}

	static function GetTicks($aData,$aType=1,$aMinor=false,$aEndPoints=false) {
		$n = count($aData);
		return self::GetTicksFromMinMax($aData[0],$aData[$n-1],$aType,$aMinor,$aEndPoints);
	}

	static function GetAutoTicks($aMin,$aMax,$aMaxTicks=10,$aMinor=false) {
		$diff = $aMax - $aMin;
		$spd = 3600*24;
		$spw = $spd*7;
		$spm = $spd*30;
		$spy = $spd*352;

		if( self::$iUseWeeks )
		$w = 'W';
		else
		$w = 'd M';

		// Decision table for suitable scales
		// First value: Main decision point
		// Second value: Array of formatting depending on divisor for wanted max number of ticks. <divisor><formatting><format-string>,..
		$tt = array(
		array($spw, array(1,DSUTILS_DAY1,'d M',2,DSUTILS_DAY2,'d M',-1,DSUTILS_DAY4,'d M')),
		array($spm, array(1,DSUTILS_DAY1,'d M',2,DSUTILS_DAY2,'d M',4,DSUTILS_DAY4,'d M',7,DSUTILS_WEEK1,$w,-1,DSUTILS_WEEK2,$w)),
		array($spy, array(1,DSUTILS_DAY1,'d M',2,DSUTILS_DAY2,'d M',4,DSUTILS_DAY4,'d M',7,DSUTILS_WEEK1,$w,14,DSUTILS_WEEK2,$w,30,DSUTILS_MONTH1,'M',60,DSUTILS_MONTH2,'M',-1,DSUTILS_MONTH3,'M')),
		array(-1, array(30,DSUTILS_MONTH1,'M-Y',60,DSUTILS_MONTH2,'M-Y',90,DSUTILS_MONTH3,'M-Y',180,DSUTILS_MONTH6,'M-Y',352,DSUTILS_YEAR1,'Y',704,DSUTILS_YEAR2,'Y',-1,DSUTILS_YEAR5,'Y')));

		$ntt = count($tt);
		$nd = floor($diff/$spd);
		for($i=0; $i < $ntt; ++$i ) {
			if( $diff <= $tt[$i][0] || $i==$ntt-1) {
				$t = $tt[$i][1];
				$n = count($t)/3;
				for( $j=0; $j < $n; ++$j ) {
					if( $nd/$t[3*$j] <= $aMaxTicks || $j==$n-1) {
						$type = $t[3*$j+1];
						$fs = $t[3*$j+2];
						list($tickPositions,$minTickPositions) = self::GetTicksFromMinMax($aMin,$aMax,$type,$aMinor);
						return array($fs,$tickPositions,$minTickPositions,$type);
					}
				}
			}
		}
	}

	static function GetTicksFromMinMax($aMin,$aMax,$aType,$aMinor=false,$aEndPoints=false) {
		self::$starthour = date('G',$aMin);
		self::$startmonth = date('n',$aMin);
		self::$startday = date('j',$aMin);
		self::$startyear = date('Y',$aMin);
		self::$endmonth = date('n',$aMax);
		self::$endyear = date('Y',$aMax);
		self::$endday = date('j',$aMax);
		self::$iMin = $aMin;
		self::$iMax = $aMax;

		if( $aType <= DSUTILS_MONTH6 ) {
			self::doMonthly($aType,$aMinor);
		}
		elseif( $aType <= DSUTILS_WEEK4 ) {
			self::doWeekly($aType,$aMinor);
		}
		elseif( $aType <= DSUTILS_DAY4 ) {
			self::doDaily($aType,$aMinor);
		}
		elseif( $aType <= DSUTILS_YEAR5 ) {
			self::doYearly($aType,$aMinor);
		}
		else {
			JpGraphError::RaiseL(24003);
		}
		// put a label at the very left data pos
		if( $aEndPoints ) {
			$tickPositions[$i++] = $aData[0];
		}

		// put a label at the very right data pos
		if( $aEndPoints ) {
			$tickPositions[$i] = $aData[$n-1];
		}

		return array(self::$tickPositions,self::$minTickPositions);
	}
}

//=============================================================================
// Class ReadFileData
//=============================================================================
Class ReadFileData {
	//----------------------------------------------------------------------------
	// Desciption:
	// Read numeric data from a file.
	// Each value should be separated by either a new line or by a specified
	// separator character (default is ',').
	// Before returning the data each value is converted to a proper float
	// value. The routine is robust in the sense that non numeric data in the
	// file will be discarded.
	//
	// Returns:
	// The number of data values read on success, FALSE on failure
	//----------------------------------------------------------------------------
	static function FromCSV($aFile,&$aData,$aSepChar=',',$aMaxLineLength=1024) {
		$rh = @fopen($aFile,'r');
		if( $rh === false ) {
			return false;
		}
		$tmp = array();
		$lineofdata = fgetcsv($rh, 1000, ',');
		while ( $lineofdata !== FALSE) {
			$tmp = array_merge($tmp,$lineofdata);
			$lineofdata = fgetcsv($rh, $aMaxLineLength, $aSepChar);
		}
		fclose($rh);

		// Now make sure that all data is numeric. By default
		// all data is read as strings
		$n = count($tmp);
		$aData = array();
		$cnt=0;
		for($i=0; $i < $n; ++$i) {
			if( $tmp[$i] !== "" ) {
				$aData[$cnt++] = floatval($tmp[$i]);
			}
		}
		return $cnt;
	}

	//----------------------------------------------------------------------------
	// Desciption:
	// Read numeric data from a file.
	// Each value should be separated by either a new line or by a specified
	// separator character (default is ',').
	// Before returning the data each value is converted to a proper float
	// value. The routine is robust in the sense that non numeric data in the
	// file will be discarded.
	//
	// Options:
	// 'separator'     => ',',
	// 'enclosure'     => '"',
	// 'readlength'    => 1024,
	// 'ignore_first'  => false,
	// 'first_as_key'  => false
	// 'escape'        => '\',   # PHP >= 5.3 only
	//
	// Returns:
	// The number of lines read on success, FALSE on failure
	//----------------------------------------------------------------------------
	static function FromCSV2($aFile, &$aData, $aOptions = array()) {
		$aDefaults = array(
            'separator'     => ',',
            'enclosure'     => chr(34),
            'escape'        => chr(92),
            'readlength'    => 1024,
            'ignore_first'  => false,
            'first_as_key'  => false
		);

		$aOptions = array_merge(
		$aDefaults, is_array($aOptions) ? $aOptions : array());

		if( $aOptions['first_as_key'] ) {
			$aOptions['ignore_first'] =  true;
		}

		$rh = @fopen($aFile, 'r');

		if( $rh === false ) {
			return false;
		}

		$aData  = array();
		$aLine  = fgetcsv($rh,
		$aOptions['readlength'],
		$aOptions['separator'],
		$aOptions['enclosure']
		/*, $aOptions['escape']     # PHP >= 5.3 only */
		);

		// Use numeric array keys for the columns by default
		// If specified use first lines values as assoc keys instead
		$keys = array_keys($aLine);
		if( $aOptions['first_as_key'] ) {
			$keys = array_values($aLine);
		}

		$num_lines = 0;
		$num_cols  = count($aLine);

		while ($aLine !== false) {
			if( is_array($aLine) && count($aLine) != $num_cols ) {
				JpGraphError::RaiseL(24004);
				// 'ReadCSV2: Column count mismatch in %s line %d'
			}

			// fgetcsv returns NULL for empty lines
			if( !is_null($aLine) ) {
				$num_lines++;

				if( !($aOptions['ignore_first'] && $num_lines == 1) && is_numeric($aLine[0]) ) {
					for( $i = 0; $i < $num_cols; $i++ ) {
						$aData[ $keys[$i] ][] = floatval($aLine[$i]);
					}
				}
			}

			$aLine = fgetcsv($rh,
			$aOptions['readlength'],
			$aOptions['separator'],
			$aOptions['enclosure']
			/*, $aOptions['escape']     # PHP >= 5.3 only*/
			);
		}

		fclose($rh);

		if( $aOptions['ignore_first'] ) {
			$num_lines--;
		}

		return $num_lines;
	}

	// Read data from two columns in a plain text file
	static function From2Col($aFile, $aCol1, $aCol2, $aSepChar=' ') {
		$lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
		if( $lines === false ) {
			return false;
		}
		$s = '/[\s]+/';
		if( $aSepChar == ',' ) {
			$s = '/[\s]*,[\s]*/';
		}
		elseif( $aSepChar == ';' ) {
			$s = '/[\s]*;[\s]*/';
		}
		foreach( $lines as $line => $datarow ) {
			$split = preg_split($s,$datarow);
			$aCol1[] = floatval(trim($split[0]));
			$aCol2[] = floatval(trim($split[1]));
		}

		return count($lines);
	}

	// Read data from one columns in a plain text file
	static function From1Col($aFile, $aCol1) {
		$lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
		if( $lines === false ) {
			return false;
		}
		foreach( $lines as $line => $datarow ) {
			$aCol1[] = floatval(trim($datarow));
		}

		return count($lines);
	}

	static function FromMatrix($aFile,$aSepChar=' ') {
		$lines = @file($aFile,FILE_IGNORE_NEW_LINES|FILE_SKIP_EMPTY_LINES);
		if( $lines === false ) {
			return false;
		}
		$mat = array();
		$reg = '/'.$aSepChar.'/';
		foreach( $lines as $line => $datarow ) {
			$row = preg_split($reg,trim($datarow));
			foreach ($row as $key => $cell ) {
				$row[$key] = floatval(trim($cell));
			}
			$mat[] = $row;
		}
		return $mat;
	}


}

define('__LR_EPSILON', 1.0e-8);
//=============================================================================
// Class LinearRegression
//=============================================================================
class LinearRegression {
	private $ix=array(),$iy=array();
	private $ib=0, $ia=0;
	private $icalculated=false;
	public $iDet=0, $iCorr=0, $iStdErr=0;

	public function __construct($aDataX,$aDataY) {
		if( count($aDataX) !== count($aDataY) ) {
			JpGraph::Raise('LinearRegression: X and Y data array must be of equal length.');
		}
		$this->ix = $aDataX;
		$this->iy = $aDataY;
	}

	public function Calc() {

		$this->icalculated = true;

		$n = count($this->ix);
		$sx2 = 0 ;
		$sy2 = 0 ;
		$sxy = 0 ;
		$sx = 0 ;
		$sy = 0 ;

		for( $i=0; $i < $n; ++$i ) {
			$sx2 += $this->ix[$i] * $this->ix[$i];
			$sy2 += $this->iy[$i] * $this->iy[$i];
			$sxy += $this->ix[$i] * $this->iy[$i];
			$sx += $this->ix[$i];
			$sy += $this->iy[$i];
		}

		if( $n*$sx2 - $sx*$sx > __LR_EPSILON ) {
			$this->ib = ($n*$sxy - $sx*$sy) / ( $n*$sx2 - $sx*$sx );
			$this->ia = ( $sy - $this->ib*$sx ) / $n;

			$sx = $this->ib * ( $sxy - $sx*$sy/$n );
			$sy2 = $sy2 - $sy*$sy/$n;
			$sy = $sy2 - $sx;

			$this->iDet = $sx / $sy2;
			$this->iCorr = sqrt($this->iDet);
			if( $n > 2 ) {
				$this->iStdErr = sqrt( $sy / ($n-2) );
			}
			else {
				$this->iStdErr = NAN ;
			}
		}
		else {
			$this->ib = 0;
			$this->ia = 0;
		}

	}

	public function GetAB() {
		if( $this->icalculated == false )
		$this->Calc();
		return array($this->ia, $this->ib);
	}

	public function GetStat() {
		if( $this->icalculated == false )
		$this->Calc();
		return array($this->iStdErr, $this->iCorr, $this->iDet);
	}

	public function GetY($aMinX, $aMaxX, $aStep=1) {
		if( $this->icalculated == false )
		$this->Calc();

		$yy = array();
		$i = 0;
		for( $x=$aMinX; $x <= $aMaxX; $x += $aStep ) {
			$xx[$i  ] = $x;
			$yy[$i++] = $this->ia + $this->ib * $x;
		}

		return array($xx,$yy);
	}

}

?>